Green Milkweed (Asclepias viridiflora)

Green comet milkweed (Asclepias viridiflora) is named after Asclepius, the Greek god of medicine, but is native to the plains and prairies of the United States. This species has deep roots that help it withstand fire and drought. The flowers are sweet-smelling and produce generous amounts of nectar. Female monarch butterflies lay their eggs on green comet milkweed, as the larvae eat only milkweed.

I. Appearance and Characteristics 

Asclepias viridiflora, is commonly known as green comet milkweed, green-flower milkweed, and green milkweed. It is a widely distributed species of milkweed (Asclepias), known from much of the eastern and central United States from Connecticut to Georgia to Arizona to Montana, as well as southern Canada and northern Mexico. The Latin specific epithet viridiflora means green-flowered.

Asclepias viridiflora is an erect to ascending herb up to 50 cm tall, with distinctive greenish-white flowers. The pods lack the warts and tubercules common on other species of Asclepias. It grows in moist to dry shaded roadsides, fields, and prairies.

It is listed as endangered in Florida, as threatened in New York (state), and as endangered in Connecticut.

II. How to Grow and Care

Green comet milkweed is a hardy perennial that thrives in full sun and well-drained soil. A key special care point is that green comet milkweed requires consistent moisture but cannot tolerate wet feet; precaution against overwatering is necessary. Green comet milkweed’s care is relatively straightforward, as it is a low-maintenance plant that is not prone to major pests or diseases.

Sunlight

Green comet milkweed thrives under full sun conditions, benefiting from its generous light intensity for most of the day. This exposure maximizes green comet milkweed’s growth potential and bolsters its overall health. Green comet milkweed showcases a degree of flexibility, tolerating partial sun. However, less than optimal light may lead to subdued growth and possibly diminished flowering. Typically found in outdoor environments, green comet milkweed should be planted where it can bask in unobstructed light. Adaptive traits such as sun-oriented leaf positioning optimize photosynthesis. The ideal installation for green comet milkweed is an open landscape that invites abundant sunshine.

Temperature

It can be planted in most areas if you would remove it after planting for just a year. The suitable temperature range for its growth is 18 to 30 ℃. It can tolerate up to 35 ℃ and withstand a minimum temperature of 8 ℃ in winter. It will stop growing below 5 ℃ and gradually die below 0 ℃.

Green comet milkweed likes a humid environment, so provide it with sufficient water in all seasons except winter. If the air humidity is too low, the leaves will gradually lose their luster.

Watering

Originating from regions with moderate moisture, green comet milkweed thrives in conditions that mimic its natural habitat, which is neither too dry nor overly humid. It exhibits a balanced water habit, showing resilience to occasional variations in watering. For optimal growth, it’s best to provide watering every week. This species typically grows outdoors and has adapted to seasonal rainfall patterns, making it an excellent candidate for gardens in temperate climates where water availability aligns with its natural growing season.

Soil

Green comet milkweed adapts to various soil environments. The most suitable soil is slightly acidic and well-drained. If the planting soil is sticky, add some leaf mold, organic fertilizer, river sand, or a similar compound and stir evenly to improve soil texture. You can also add a little soil at the base of the plant to encourage growth. This will prevent plant lodging and provide more nutrients to the roots.

Fertilizing

To foster robust growth and vibrant blooms in green comet milkweed, a balanced nutrition fertilizer is ideal. Apply a diluted half-strength solution every four weeks during the growing season, reducing frequency in winter. Benefits include strengthened resilience and enriched flowering. Over-fertilization can harm green comet milkweed, so adhere to suggested quantities. Monitor growth stages, as immature green comet milkweed require less. Employ slow-release formulas to temper nutrient delivery. An effective regimen enhances green comet milkweed’s vitality, ensuring a spectacular garden display.

Planting Instructions

Green comet milkweed can be sown in spring, planted in flower pots or placed directly in the garden. You can keep seeded pots indoors. Sow at warmer temperatures for best results. The seeding depth is about 2.5 cm. Press the soil slightly, so that the soil and the seed make firm contact. After sowing, water the seeds thoroughly. Generally, they will germinate after two weeks with a germination rate of about 80-90%.

When the seeds in the pot germinate with 2-3 pairs of leaves, they can be transplanted into the ground. When transplanting, keep the soil on the roots to avoid damaging the root system. Remember to water thoroughly after planting. Green comet milkweed grows best in a ventilated environment, such as by a road, wall, or window. Without good ventilation, pests will appear, which can threaten the plant’s growth.

Pruning

Regularly remove infected plants and wilting leaves to keep green comet milkweed healthy. If you are located in a tropical or subtropical climate, you can cut off branches in early spring to promote germination. Given the high toxicity of green comet milkweed, wear gloves when handling plants to prevent poisoning. Keep green comet milkweed away from children, avoid direct contact, and do not eat the plant.

Propagation

Green comet milkweed thrives when propagated through sowing. Gardeners should collect the seeds after the pods mature and dry on the plant. Prior to sowing, it is essential to cold stratify the seeds for a few weeks to mimic winter conditions, enhancing germination rates. Sow seeds superficially in a well-draining soil mixture and keep the medium consistently moist. The appropriate germination environment can be achieved with light cover, ensuring that the young seedlings receive adequate but not direct sunlight to prevent scorching. Regular monitoring and tender care will help establish healthy green comet milkweed plants.

Transplanting

Transplant green comet milkweed in the awakening days of spring through to the caress of late spring breezes, selecting a sun-kissed location with well-draining soil. Offer green comet milkweed a new home early to establish robust roots before summer’s heat.

III. Uses and Benefits 

The Blackfoot apply a poultice of chewed roots to swellings, rashes, sore gums of nursing infants, and sore eyes. They also chew the root for sore throats, use the plant to spice soups, and use the fresh roots for food. The Brulé Lakota give pulverized roots to children with diarrhea, and an infusion of the whole plant is taken by mothers to increase their milk.